Why did the children make the White Walkers?

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Tags

1. #walkers
2. #forest
3. #heroes
4. #years
5. #coming
6. #children
7. #essos
8. #arrived
9. #first
10. #magic
11. #white
12. #since
13. #waged
14. #powerful
15. #protect
16. #thousands
17. #created
18. #preceding
19. #untested